JPH01262848A - Supersonic probe and its manufacture - Google Patents

Abstract

PURPOSE:To attain the separation of an oscillator and the fetching if a lead line as well by forming a bump with using metal such as Au or Cu, pressure- contacting a piezoelectric oscillator and a flexible print board, after that, adhering them and dividing the piezoelectric oscillator in a prescribed pitch with using a dicer. CONSTITUTION:The piezoelectric oscillator is two-dimensionally divided and a bump 2 is formed in each element. Even in a multi-layer flexible print substrate, the bump 2 is formed in the same pitch and the oscillator and substrate are bonded with being pressure-contacted. The bump is formed near the center of each element. It is same in the flexible print board side. A common electrode is provided on the upper surface of the respective piezoelectric oscillators 1 and the lower surfaces of the respective piezoelectric oscillators 1 are electrically connected by the wiring of a print board 3 respectively. Thus, when the oscillator is divided, the bump goes to be a supporting stand and the oscillator is prevented from being dispersed after the division. Simultaneously, the two-dimensional conduction of a signal line can be executed.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to an ultrasonic probe for transmitting and receiving ultrasonic waves used in ultrasonic diagnostic equipment, etc. The present invention relates to an ultrasonic probe equipped with an array of transducers and a method for manufacturing the same.

(Prior art) Ultrasonic diagnostic equipment scans the inside of a subject using ultrasound,
This method obtains tomographic images by detecting the reflected waves, and is rapidly becoming popular due to its real-time and non-invasive diagnostic capabilities. There are two types of scanning: mechanical scanning, which is performed by mechanically moving an ultrasound probe, and electronic scanning, which is performed by using an array of transducers to electronically switch and control the delay time. Electronic scanning has become mainstream for improvement. As an electronic scanning method.

Broadly speaking, there are linear electronic scanning and sector electronic scanning. Techniques for achieving high resolution in the scanning direction (azimuthal direction) in electronic scanning include the reception dynamic focus method, which sequentially switches the convergence point of the ultrasound beam according to the time corresponding to the depth inside the subject during reception; There is a multi-stage focusing method that connects images near the convergence point by repeating transmission and reception while changing the convergence point. However, in the direction perpendicular to the scanning plane, that is, in the slice direction, a method is used in which the ultrasound beam is converged to one point using an acoustic lens, and there is a problem in that the width of the ultrasound beam becomes wider before and after the convergence point. In the slicing direction, a good image can be obtained near the convergence point of the acoustic lens, but the image becomes blurred before and after the convergence point where the width of the ultrasound beam becomes wider, and the microstructures of small blood vessels etc. cannot be clearly visualized. This is the result.

In order to improve these drawbacks, attempts have been made to improve the resolution in the same way as in the scanning direction by using a two-dimensional array of transducers and applying reception dynamic focus and multi-step focusing in the slice direction in addition to the scanning direction. being done.

By the way, the method for manufacturing such an ultrasonic probe is as follows. When using a one-dimensional array vibrator, the vibrator is bonded to a backing material, the backing material is used as a fixed plate (supporting base), and a dicer is used to divide the shaken J element into m sections in the scanning direction. The connection of the lead wires has been realized by, for example, using a flexible printed board 1 to connect the chamfered corners of the backing material to the electrodes on the back surface of the piezoelectric vibrator with a conductive adhesive or solder. When this manufacturing method is applied to a two-dimensionally arrayed vibrator, the vibrator is bonded to a backing material, and the backing material is used as a support.
The transducer is divided into m parts in the scanning direction and n parts in the slicing direction using a dicer. In this case, since it is also divided in the slice direction, the connection of the rieet wires cannot be realized by the above-mentioned conventional method.

(Problem to be Solved by the Invention) When manufacturing an ultrasonic probe having two-dimensionally arrayed transducers as described above, it is necessary to divide the transducers in both the scanning direction and the slicing direction. When a backing material such as ferrite rubber was used as a support base, there was a problem that lead wires could not be connected.

SUMMARY OF THE INVENTION An object of the present invention is to solve such problems and provide an ultrasonic probe having a two-dimensional array of transducers that allows the transducers to be divided and lead wires to be taken out, and a method for manufacturing the same.

[Structure of the invention]

(Means for Solving the Problems) The present invention forms bumps using Au or Cu metal at a predetermined pitch on a piezoelectric vibrator, and also forms bumps using Au or Cu metal at a similar pitch on a flexible printed board. Cu
Bumps are formed using metals such as piezoelectric vibration! l!
After bonding the 11th child and the flexible printed board by pressure bonding,
Divide the piezoelectric vibrator into two pieces at a predetermined pitch using a dicer.
The present invention is characterized in that an ultrasonic probe having a dimensional array transducer is manufactured.

(Function) The present invention makes it possible to take out lead wires two-dimensionally, and also arrange them two-dimensionally on the ferrite rubber etc. that conventionally served as a support for the vibrator when splitting. The raised bumps serve as a support base.

(Example) FIG. 1 is a structural diagram of an ultrasonic probe according to an example of the present invention. The piezoelectric vibrator is divided two-dimensionally, bumps are formed on each element, and a multilayer flexible printed board with the same pitch! Bumps are also formed on the board, which are bonded by pressure bonding.
For example, high voltage SW etc. via a multilayer printed circuit board.
IC is mounted.

FIG. 2 shows a top view of a state in which bumps are formed at the piezoelectric vibration tJJ junction before division. A bump is formed near the center of each element. This also applies to the flexible printed board side. A common electrode (not shown) is provided on the -F surface of each piezoelectric vibrator 1, and the lower surface of each piezoelectric vibrator 1 is electrically connected to each other by wiring on a printed board.

FIG. 3 shows a structural diagram of the bump. An insulating layer with a thickness of about 1 to 1.5 μm is formed on the piezoelectric vibrator by printing, and an i-pad with a width of about 1007 m is formed on the insulating layer by printing. Furthermore, using Au, Cu, etc., a height of about 3
A bump of around 0 μm is formed. After that, the oscillator is polarized. Bumps are also formed on the flexible printed board side using a similar method.

After forming the bumps using the above method, the pendulum fJj and the printed board are bonded together by pressure bonding. Thereafter, the vibrator is divided at a predetermined pitch using a dicer.

〔Effect of the invention〕

According to the present invention, an ultrasonic probe whose transducer can be easily divided and two-dimensionally wired can be obtained.

Further, according to the present invention, when the vibrator is divided, the bumps serve as a support base, and the vibrator will not be scattered after being divided. At the same time, it also becomes possible to draw out two-dimensional signal lines, which was previously impossible.

Although this method is basically air backing,
By pouring resin etc into that space.

It is also possible to obtain a damping effect equivalent to the conventional one.

[Brief explanation of the drawing]

Fig. 1 is a structural diagram of an ultrasonic probe according to an embodiment of the present invention, Fig. 2 is a top view of a transducer with bumps formed on the transducer before division, and Fig. 3 is a structural diagram of the bumps. It is. 1...Piezoelectric vibrator 2...Bump 3/Printed board 4...Insulating layer 5/Pad agent Patent attorney Noriyoshi Chika Dosage Mitsuyuki Matsuyama

Claims (2)

[Claims] (1) A flexible printed board, a plurality of bumps arranged two-dimensionally at predetermined intervals on the flexible printed board, and two-dimensionally arranged piezoelectric vibrators each corresponding to each bump. Ultrasonic probe. (2) In a two-dimensionally arrayed vibrator divided along two orthogonal directions of the piezoelectric vibrator and a flexible printed board connected oppositely to the vibrator, the piezoelectric vibrator and the flexible printed board are arranged at a predetermined pitch. 1. A method of manufacturing an ultrasonic probe, comprising forming bumps, connecting the bumps by crimping, and then dividing a piezoelectric vibrator at a predetermined pitch.